Toyota Avalon (XX50): Front Airbag Sensor Lost Communication (LH) (B1617,B1618). Curtain Shield Airbag Sensor (RH) (B1630). Curtain Shield Airbag Sensor Lost Communication (RH) (B1632,B1633)

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Vehicle Interior / Supplemental Restraint Systems / Airbag System(for Gasoline Model) / Front Airbag Sensor Lost Communication (LH) (B1617,B1618). Curtain Shield Airbag Sensor (RH) (B1630). Curtain Shield Airbag Sensor Lost Communication (RH) (B1632,B1633)

Front Airbag Sensor Lost Communication (LH) (B1617,B1618)

DESCRIPTION

The front airbag sensor LH circuit consists of the airbag ECU assembly and front airbag sensor LH.

The front airbag sensor LH detects impacts to the vehicle and sends signals to the airbag ECU assembly to determine if the airbags and pretensioners should be deployed.

These DTCs are stored when a malfunction is detected in the front airbag sensor LH circuit.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Test Mode / Check Mode

B1617

Front Airbag Sensor Lost Communication (LH)

  • The airbag ECU assembly detects a line short, short to ground or B+, or an open in the front airbag sensor LH circuit.
  • Front airbag sensor LH malfunction
  • Airbag ECU assembly malfunction
  • Instrument panel wire
  • Engine room main wire
  • Front airbag sensor LH
  • Airbag ECU assembly

Comes on

Does not apply to test/check mode

B1618

Front Airbag Sensor Initialization Error (LH)

  • The airbag ECU assembly detects a line short, short to ground or B+, or an open in the front airbag sensor LH circuit.
  • Front airbag sensor LH malfunction
  • Airbag ECU assembly malfunction
  • Instrument panel wire
  • Engine room main wire
  • Front airbag sensor LH
  • Airbag ECU assembly

Comes on

Does not apply to test/check mode

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

Click here

PROCEDURE

1.

CHECK CONNECTION OF CONNECTORS

(a) Turn the engine switch off.

(b) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(c) Check that the connectors are properly connected to the airbag ECU assembly and front airbag sensor LH. Also check that the connectors that link the engine room main wire and instrument panel wire are properly connected.

OK:

The connectors are properly connected.

NG

CONNECT CONNECTORS PROPERLY

OK

2.

CHECK CONNECTORS

(a) Disconnect the connectors from the airbag ECU assembly and front airbag sensor LH. Also disconnect the connectors that link the engine room main wire and instrument panel wire.

(b) Check that the terminals of the connectors are not deformed or damaged.

OK:

The terminals are not deformed or damaged.

NG

REPLACE INSTRUMENT PANEL WIRE OR ENGINE ROOM MAIN WIRE

OK

3.

CHECK FRONT AIRBAG SENSOR LH CIRCUIT

(a) Connect the connectors that link the engine room main wire and instrument panel wire.

*1

Front Airbag Sensor LH

*2

Airbag ECU Assembly

*3

Engine Room Main Wire

*4

Instrument Panel Wire

*5

Service Wire

*a

Front view of wire harness connector

(to Airbag ECU Assembly)

*b

Front view of wire harness connector

(to Front Airbag Sensor LH)

(b) Connect the cable to the negative (-) battery terminal.

(c) Turn the engine switch on (IG).

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

A38-2 (+SL) - Body ground

Engine switch on (IG)

Below 1 V

A38-1 (-SL) - Body ground

Engine switch on (IG)

Below 1 V

(e) Turn the engine switch off.

(f) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(g) Using a service wire, connect terminals 30 (+SL) and 31 (-SL) of connector B.

NOTICE:

Do not forcibly insert the service wire into the terminals of the connector when connecting the wire.

(h) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A38-2 (+SL) - A38-1 (-SL)

Always

Below 1 Ω

(i) Disconnect the service wire from connector B.

(j) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A38-2 (+SL) - A38-1 (-SL)

Always

1 MΩ or higher

A38-2 (+SL) - Body ground

Always

1 MΩ or higher

A38-1 (-SL) - Body ground

Always

1 MΩ or higher

NG

GO TO STEP 5

OK

4.

CHECK FRONT AIRBAG SENSOR LH

(a) Connect the connector to the airbag ECU assembly.

*1

Front Airbag Sensor RH

*2

Airbag ECU Assembly

(b) Interchange the front airbag sensor LH with RH and connect the connectors.

(c) Connect the cable to the negative (-) battery terminal.

(d) Turn the engine switch on (IG), and wait for at least 60 seconds.

(e) Clear the DTCs stored in memory.

Body Electrical > SRS Airbag > Clear DTCs

(f) Turn the engine switch off.

(g) Turn the engine switch on (IG), and wait for at least 60 seconds.

(h) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

HINT:

Codes other than DTCs B1612, B1613, B1617 and B1618 may be output at this time, but they are not related to this check.

Result

Proceed to

DTCs B1612, B1613, B1617 and B1618 are not output.

A

DTC B1617 or B1618 is output.

B

DTC B1612 or B1613 is output.

C

(i) Turn the engine switch off.

(j) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(k) Return the front airbag sensor LH and RH to their original positions and connect the connectors.

A

USE SIMULATION METHOD TO CHECK

B

REPLACE AIRBAG ECU ASSEMBLY

C

REPLACE FRONT AIRBAG SENSOR LH

5.

CHECK INSTRUMENT PANEL WIRE

(a) Disconnect the instrument panel wire connector from the engine room main wire.

*1

Front Airbag Sensor LH

*2

Airbag ECU Assembly

*3

Engine Room Main Wire

*4

Instrument Panel Wire

*5

Service Wire

*a

Front view of wire harness connector

(to Airbag ECU Assembly)

*b

Front view of wire harness connector

(to Engine Room Main Wire)

(b) Connect the cable to the negative (-) battery terminal.

(c) Turn the engine switch on (IG).

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

AG5-2 (+SL) - Body ground

Engine switch on (IG)

Below 1 V

AG5-4 (-SL) - Body ground

Engine switch on (IG)

Below 1 V

(e) Turn the engine switch off.

(f) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(g) Using a service wire, connect terminals 30 (+SL) and 31 (-SL) of connector B.

NOTICE:

Do not forcibly insert the service wire into the terminals of the connector when connecting the wire.

(h) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

AG5-2 (+SL) - AG5-4 (-SL)

Always

Below 1 Ω

(i) Disconnect the service wire from connector B.

(j) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

AG5-2 (+SL) - AG5-4 (-SL)

Always

1 MΩ or higher

AG5-2 (+SL) - Body ground

Always

1 MΩ or higher

AG5-4 (-SL) - Body ground

Always

1 MΩ or higher

OK

REPLACE ENGINE ROOM MAIN WIRE

NG

REPLACE INSTRUMENT PANEL WIRE

Curtain Shield Airbag Sensor (RH) (B1630)

DESCRIPTION

The side collision sensor RH circuit (bus 1) consists of the airbag ECU assembly, side airbag pressure sensor RH and side No. 2 airbag sensor RH.

The side airbag pressure sensor RH and side No. 2 airbag sensor RH detect impacts to the vehicle and send signals to the airbag ECU assembly to determine if the airbags and pretensioners should be deployed.

DTC B1630 is stored when a malfunction is detected in the side No. 2 airbag sensor RH.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Test Mode / Check Mode

B1630

Curtain Shield Airbag Sensor (RH)

  • Side No. 2 airbag sensor RH malfunction
  • Airbag ECU assembly malfunction
  • Side No. 2 airbag sensor RH
  • Airbag ECU assembly

Comes on

Does not apply to test/check mode

WIRING DIAGRAM

Click here

CAUTION / NOTICE / HINT

NOTICE:

After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

Click here

PROCEDURE

1.

CHECK SIDE NO. 2 AIRBAG SENSOR RH

(a) Turn the engine switch off.

*1

Side No. 2 Airbag Sensor LH

*2

Airbag ECU Assembly

(b) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(c) Interchange the side No. 2 airbag sensor RH with LH and connect the connectors.

(d) Connect the cable to the negative (-) battery terminal.

(e) Turn the engine switch on (IG), and wait for at least 60 seconds.

(f) Clear the DTCs stored in memory.

Body Electrical > SRS Airbag > Clear DTCs

(g) Turn the engine switch off.

(h) Turn the engine switch on (IG), and wait for at least 60 seconds.

(i) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

HINT:

Codes other than DTCs B1630 and B1635 may be output at this time, but they are not related to this check.

Result

Proceed to

DTC B1630 is output.

A

DTC B1635 is output.

B

DTCs B1630 and B1635 are not output.

C

(j) Turn the engine switch off.

(k) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(l) Return the side No. 2 airbag sensor RH and LH to their original positions and connect the connectors.

A

REPLACE AIRBAG ECU ASSEMBLY

B

REPLACE SIDE NO. 2 AIRBAG SENSOR RH

C

USE SIMULATION METHOD TO CHECK

Curtain Shield Airbag Sensor Lost Communication (RH) (B1632,B1633)

DESCRIPTION

The side collision sensor RH circuit (bus 1) consists of the airbag ECU assembly, side airbag pressure sensor RH and side No. 2 airbag sensor RH.

The side airbag pressure sensor RH and side No. 2 airbag sensor RH detect impacts to the vehicle and send signals to the airbag ECU assembly to determine if the airbags and pretensioners should be deployed.

These DTCs are stored when a malfunction is detected in the side collision sensor RH circuit (bus 1).

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Test Mode / Check Mode

B1632

Curtain Shield Airbag Sensor Lost Communication (RH)

  • The airbag ECU assembly detects a line short, short to ground or B+, or an open in the side collision sensor RH circuit (bus 1).
  • Side airbag pressure sensor RH malfunction
  • Side No. 2 airbag sensor RH malfunction
  • Airbag ECU assembly malfunction
  • Floor wire
  • Front door wire RH
  • Side airbag pressure sensor RH
  • Side No. 2 airbag sensor RH
  • Airbag ECU assembly

Comes on

Does not apply to test/check mode

B1633

Curtain Shield Airbag Sensor Initialization Error (RH)

  • The airbag ECU assembly detects a line short, short to ground or B+, or an open in the side collision sensor RH circuit (bus 1).
  • Side airbag pressure sensor RH malfunction
  • Side No. 2 airbag sensor RH malfunction
  • Airbag ECU assembly malfunction
  • Floor wire
  • Front door wire RH
  • Side airbag pressure sensor RH
  • Side No. 2 airbag sensor RH
  • Airbag ECU assembly

Comes on

Does not apply to test/check mode

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

Click here

PROCEDURE

1.

CHECK CONNECTION OF CONNECTORS

(a) Turn the engine switch off.

(b) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(c) Check that the connectors are properly connected to the airbag ECU assembly, side airbag pressure sensor RH and side No. 2 airbag sensor RH. Also check that the connectors that link the floor wire and front door wire RH are properly connected.

OK:

The connectors are properly connected.

NG

CONNECT CONNECTORS PROPERLY

OK

2.

CHECK CONNECTORS

(a) Disconnect the connectors from the airbag ECU assembly, side airbag pressure sensor RH and side No. 2 airbag sensor RH. Also disconnect the connectors that link the floor wire and front door wire RH.

(b) Check that the terminals of the connectors are not deformed or damaged.

OK:

The terminals are not deformed or damaged.

NG

REPLACE FLOOR WIRE OR FRONT DOOR WIRE RH

OK

3.

CHECK FLOOR WIRE

(a) Connect the cable to the negative (-) battery terminal.

*1

Side No. 2 Airbag Sensor RH

*2

Airbag ECU Assembly

*3

Floor Wire

*4

Service Wire

*a

Front view of wire harness connector

(to Airbag ECU Assembly)

*b

Front view of wire harness connector

(to Side No. 2 Airbag Sensor RH)

(b) Turn the engine switch on (IG).

(c) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

K30-4 (BCR+) - Body ground

Engine switch on (IG)

Below 1 V

K30-3 (BCR-) - Body ground

Engine switch on (IG)

Below 1 V

(d) Turn the engine switch off.

(e) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(f) Using a service wire, connect terminals 25 (BBR+) and 26 (BBR-) of connector B.

NOTICE:

Do not forcibly insert the service wire into the terminals of the connector when connecting the wire.

(g) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K30-4 (BCR+) - K30-3 (BCR-)

Always

Below 1 Ω

(h) Disconnect the service wire from connector B.

(i) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K30-4 (BCR+) - K30-3 (BCR-)

Always

1 MΩ or higher

K30-4 (BCR+) - Body ground

Always

1 MΩ or higher

K30-3 (BCR-) - Body ground

Always

1 MΩ or higher

NG

REPLACE FLOOR WIRE

OK

4.

CHECK WIRE HARNESS

(a) Connect the connectors that link the floor wire and front door wire RH.

*1

Side Airbag Pressure Sensor RH

*2

Side No. 2 Airbag Sensor RH

*3

Front Door Wire RH

*4

Floor Wire

*5

Service Wire

*a

Front view of wire harness connector

(to Side No. 2 Airbag Sensor RH)

*b

Front view of wire harness connector

(to Side Airbag Pressure Sensor RH)

(b) Connect the cable to the negative (-) battery terminal.

(c) Turn the engine switch on (IG).

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

K30-1 (BDR+) - Body ground

Engine switch on (IG)

Below 1 V

K30-2 (BDR-) - Body ground

Engine switch on (IG)

Below 1 V

(e) Turn the engine switch off.

(f) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(g) Using a service wire, connect terminals 2 (BDR+) and 1 (BDR-) of connector E.

NOTICE:

Do not forcibly insert the service wire into the terminals of the connector when connecting the wire.

(h) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K30-1 (BDR+) - K30-2 (BDR-)

Always

Below 1 Ω

(i) Disconnect the service wire from connector E.

(j) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K30-1 (BDR+) - K30-2 (BDR-)

Always

1 MΩ or higher

K30-1 (BDR+) - Body ground

Always

1 MΩ or higher

K30-2 (BDR-) - Body ground

Always

1 MΩ or higher

NG

GO TO STEP 7

OK

5.

CHECK SIDE NO. 2 AIRBAG SENSOR RH

(a) Connect the connectors to the side airbag pressure sensor RH and airbag ECU assembly.

*1

Side No. 2 Airbag Sensor LH

*2

Airbag ECU Assembly

(b) Interchange the side No. 2 airbag sensor RH with LH and connect the connectors.

(c) Connect the cable to the negative (-) battery terminal.

(d) Turn the engine switch on (IG), and wait for at least 60 seconds.

(e) Clear the DTCs stored in memory.

Body Electrical > SRS Airbag > Clear DTCs

(f) Turn the engine switch off.

(g) Turn the engine switch on (IG), and wait for at least 60 seconds.

(h) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

HINT:

Codes other than DTCs B1632, B1633, B1637 and B1638 may be output at this time, but they are not related to this check.

Result

Proceed to

DTC B1632 or B1633 is output.

A

DTC B1637 or B1638 is output.

B

DTCs B1632, B1633, B1637 and B1638 are not output.

C

(i) Turn the engine switch off.

(j) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(k) Return the side No. 2 airbag sensor RH and LH to their original positions and connect the connectors.

B

REPLACE SIDE NO. 2 AIRBAG SENSOR RH

C

USE SIMULATION METHOD TO CHECK

A

6.

CHECK SIDE AIRBAG PRESSURE SENSOR RH

(a) Interchange the side airbag pressure sensor RH with LH and connect the connectors.

*1

Side Airbag Pressure Sensor LH

*2

Side No. 2 Airbag Sensor RH

(b) Connect the cable to the negative (-) battery terminal.

(c) Turn the engine switch on (IG), and wait for at least 60 seconds.

(d) Clear the DTCs stored in memory.

Body Electrical > SRS Airbag > Clear DTCs

(e) Turn the engine switch off.

(f) Turn the engine switch on (IG), and wait for at least 60 seconds.

(g) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

HINT:

Codes other than DTCs B1632, B1633, B1637 and B1638 may be output at this time, but they are not related to this check.

Result

Proceed to

DTC B1632 or B1633 is output.

A

DTC B1637 or B1638 is output.

B

DTCs B1632, B1633, B1637 and B1638 are not output.

C

(h) Turn the engine switch off.

(i) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(j) Return the side airbag pressure sensor RH and LH to their original positions and connect the connectors.

A

REPLACE AIRBAG ECU ASSEMBLY

B

REPLACE SIDE AIRBAG PRESSURE SENSOR RH

C

USE SIMULATION METHOD TO CHECK

7.

CHECK FLOOR WIRE

(a) Disconnect the floor wire connector from the front door wire RH.

*1

Side Airbag Pressure Sensor RH

*2

Side No. 2 Airbag Sensor RH

*3

Front Door Wire RH

*4

Floor Wire

*5

Service Wire

*a

Front view of wire harness connector

(to Side No. 2 Airbag Sensor RH)

*b

Front view of wire harness connector

(to Front Door Wire RH)

(b) Connect the cable to the negative (-) battery terminal.

(c) Turn the engine switch on (IG).

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

IK1-23 (BDR+) - Body ground

Engine switch on (IG)

Below 1 V

IK1-41 (BDR-) - Body ground

Engine switch on (IG)

Below 1 V

(e) Turn the engine switch off.

(f) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(g) Using a service wire, connect terminals 1 (BDR+) and 2 (BDR-) of connector B.

NOTICE:

Do not forcibly insert the service wire into the terminals of the connector when connecting the wire.

(h) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

IK1-23 (BDR+) - IK1-41 (BDR-)

Always

Below 1 Ω

(i) Disconnect the service wire from connector B.

(j) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

IK1-23 (BDR+) - IK1-41 (BDR-)

Always

1 MΩ or higher

IK1-23 (BDR+) - Body ground

Always

1 MΩ or higher

IK1-41 (BDR-) - Body ground

Always

1 MΩ or higher

OK

REPLACE FRONT DOOR WIRE RH

NG

REPLACE FLOOR WIRE

Front Airbag Sensor (RH) (B1610). Front Airbag Sensor Lost Communication (RH) (B1612,B1613). Front Airbag Sensor (LH) (B1615)

Curtain Shield Airbag Sensor (LH) (B1635). Curtain Shield Airbag Sensor Lost Communication (LH) (B1637,B1638). Occupant Classification System Malfunction (B1650,B165A)

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Toyota Avalon (XX50) 2019-2022 Service & Repair Manual

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